Active façades to obtain comfortable low energy dwellings

F.G.H. Koene, F.A.T.M. Ligthart, K.J. Strootman, M.T.N. Ottenbros, and R. Schuitema, Energy Research Centre of the Netherlands (ECN)

Keywords

active façade, energy saving, indoor comfort, sun shading, ventilation, night cooling, rotating research facility

Abstract

Where a conventional façade is usually a passive boundary between the indoor and outdoor climate, an 'active' façade responds to (and anticipates on) changes in indoor and outdoor conditions. In cooperation with our project partner, De Vries Kozijnen, four different 'active' façades are built. The façades are of prefab construction, ensuring a much higher product quality than is possible with on-site assembly of components. The functions of the different components can be tuned to cooperate. Prefab construction also allows for an aesthetic and appealing look.

The four active façades are integrated in a research facility on the ECN premises, where they have been tested for over a year. The techniques used appear to function well although the sun shading in one design is prone to improvement.

Simulations show the potential of the façades to reduce energy consumption and improve indoor comfort in a regular dwelling. With fully functional 'active' façades, using a CO2 sensor to guard and control indoor air quality, the heating demand of 17 kWh/m2.a is nearly as low as that of a Passive House (15 kWh/m2.a), while overheating is practically eliminated.